View Full Version : Egads! 3 Phase power supply?

10-02-2003, 02:10 AM
I found a power supply with the correct output for my motors. But it has an input of:
"Input Voltages of 208 VAC 3PH 15A 50/60 HZ and 380 VAC 3PH 15A 50/60 HZ".

I assume the 3PH means its 3 phase. I know nothing of 3 phase. Assuming I have my cnc router right next to the breaker box in my garage...is it a big deal to get 3 phase power?

What would I have to do?

10-02-2003, 06:23 AM
Call the power company...unless you live in the sticks, 3 leg power is there...

I asked our Motion control guy about 3 Ph power and Phase converters. A Phase converter will reduce the power output and life of a motor...by as much as 20%. Theres better ways to do it..;)

10-02-2003, 07:31 AM
If you live in a house (not a factory) 3 phase is not an option. It's for industry. They won't hook you up to 3 phase and you can't afford it if they could.

Buy a single phase power supply.


10-02-2003, 07:58 AM
Balsaman quote "Buy a single phase power supply."

Yep, it is the only cost effective option you have.


10-02-2003, 08:54 AM
You could check out news group
many of the folks over there have phase converters in their shops.
There seem to be 2 ways to do it:
1. electronically ($$$): bring in single phase, rectify, modulate, transform, output. Supplied power is as good as it can be up to the rated load.
2. with a 3 phase motor: apply single phase to 2 leads of a 3-phase motor, take 3-phase power off all 3 leads of motor. Supplied power varies with load. Yes, this will reduce the life of your target motor. But if its rated life is 10,000 hours, cutting that even in half, 5,000 hours in a hobby machine is a loooooong time :) .

robotic regards,

= = = = =
"The waist is a terrible thing to mind."
- - Ziggy

oops - misread the original post - thought you had a 3-phase motor you needed power for, not a 3-phase power supply you needed a motor for ...

10-02-2003, 09:37 PM
When I first started out 3ph. power wasn't availible to me so I had no choice but a phase coverter, contacted George J. Snyder Co. who hooked me with one and it's been 14 yrs (32hrs. week,20hrs. weekends). I've never burnt out a motor and right now it powers a cnc turning center, VMC, small grinder, 13 inch lathe, Bridgeport miller and Snow tapping center. E-mail me if you want and I'll get you a no. and address. Stay away from static conveters and go rotor if you can.